1. Field of the Invention
The present invention relates to hydrocarbon cracking catalysts and uses thereof in catalytic cracking processes.
2. Description of the Prior Art
Hydrocarbon cracking catalysts comprising a zeolite dispersed in a siliceous matrix are known. See, for example, U.S. Pat. No. 3,140,249 and U.S. Pat. No. 3,352,796.
U.S. Pat. No. 4,137,152 discloses a cracking process utilizing a mixture of faujasite and mordenite.
U.S. Pat. No. 3,894,934 discloses catalytic cracking of hydrocarbons utilizing a large pore zeolite and a small pore zeolite such as zeolite ZSM-5. These zeolites may be dispersed in a common matrix.
U.S. Pat. No. 3,871,993 discloses a process for upgrading the octane value of naphtha utilizing a shape selective catalyst such as zeolite ZSM-5, ZSM-11, ZSM-12, ZSM-21, mordenite, etc., in the absence of added hydrogen.
U.S. Pat. No. 3,702,886 discloses use of ZSM-5 zeolite alone or in combination with other materials such as zeolites or inert materials for catalytic cracking of hydrocarbons, see particularly columns 6 and 7.
U.S. Pat. No. 3,804,747 discloses a hydrocarbon conversion process utilizing a mixture of zeolites X and Y.
U.S. Pat. No. 3,758,403 discloses catalytic cracking comprising a large pore zeolite, such as zeolite Y, and a small pore zeolite, such as ZSM-5, in a siliceous matrix. The matrix may be active or inactive, such as silica-alumina or alumina. The use of the ZSM-5 type zeolite results in obtaining a fuel of increased octane number.
U.S. Pat. No. 3,769,202 discloses a combination catalyst comprising a mixture of two different zeolites, one having a pore size greater than 8 Angstroms and the other having a pore size of less than 7 Angstroms. The zeolites are mixed with an inorganic oxide matrix such as silica-alumina. The catalyst is suitable for cracking and hydrocracking of the hydrocarbons.
U.S. Pat. No. 3,925,195 discloses a cracking process utilizing a catalyst comprising a mixture of rare earth hydrogen Y-type zeolite, and hydrogen or transition metal exchanged mordenite, calcium exchanged type A zeolite, or hydrogen exchanged erionite and an amorphous matrix.
U.S. Pat. No. 3,764,520 discloses a catalyst comprising a mixture of two different zeolites, one having a pore size within the range of 6 to 15 Angstroms and the other having a pore size of less than 6 Angstroms in combination with an inorganic oxide support. The catalyst is useful for hydrocarbon conversion processes to give increased selectivity.